What was the Oracle of Delphi?

Answer 1

A snake in a cave which was interrogated by a priestess who posed the questions to it asked by embassies from the Greek cities.

Delphi had a good intelligence network throughout the Greek cities, so they knew what questions were going to be asked by the time the ambassadors arrived, and so could cook up appropriate obscure two-way answers for the priestess to give. Being obscure and with two meanings, the answer would always turn out right, whatever eventually happened. The gifts which the ambassadors brought kept Delphi prosperous.

Answer 2

The Oracle welcomed people who came to the Temple of Apollo, the God of Prophecies, and would tell people the future. The Oracle would often speak in riddles, and sometimes, her predictions were accurate. It was believed for many years that the smoke that often was seen billowing up from the floor of the room, which came from the caverns bellow, gave the Oracle a "high" effect for being in that room all day. In recent years, it was proven that the fumes in the chamber did not affect her, and were completely harmless.